THE TEETH. 



193 



all the incisors fully up, until it is five years old. It will be seen, 

 however, in this mouth of four years, that the two central pairs are 

 beginning to be worn down at the edges, and that in a flat direction, 

 or somewhat inclinino- towards the inside. 



THREE YEARS. PAST. 



FOUR YEARS. PAST. 



At five years old, the teeth are all fully grown, but this mark has 

 extended over the whole set, and all the teeth are a little flattened 

 at the top ; while on the two centre ones there begins to be a dis- 

 tinct darker line in the middle, bounded by a line of harder bone. 



From this time the age for a year or two can only be guessed at, 

 and a great deal will depend up- 

 on the manner in which the ani- 

 mal is fed. The beast most out, 

 and compelled most to use his 

 incisor teeth, will have them 

 •worn farthest down. As a 

 general rule, but admitting of 

 many exceptions, at seven years 

 old, this hne is becoming broad- 

 est and more irregular in all of 

 the teeth; and a second and 

 broader, and more circular mark 

 appears within the centre of the 

 former one, the most distinct in 

 the central, or two central pairs 

 — and which at eight years has 

 spread over the six central inci- 

 sors. 



9 



FTVE YEARS. PAST. 



